Get a dedicated host for the security tracker

As mentioned in https://github.com/NixOS/nix-security-tracker/issues/850, we want to move the [Security tracker](https://tracker.security.nixos.org/) hosts (both staging and production) from Hetzner Cloud VMs to a dedicated host since this makes more sense nowadays. We spun up the cloud VMs using nixos-anywhere, so we're fine with using it for this host as well. If myself (@Erethon) and @fricklerhandwerk could be given access to manage this host it would be ideal. If this is not possible, it's ok since the plan is to spin up VMs and we don't anticipate needing console access to the host itself after the initial provisioning.